Advertisements
Advertisements
Question
Verify the following equalities:
sin2 60° + cos2 60° = 1
Solution
sin 60° = `sqrt(3)/2`, cos 60° = `1/2`
L.H.S = sin2 60° + cos2 60°
= `(sqrt(3)/2)^2 + (1/2)^2`
= `3/4 + 1/4`
= `4/4`
= 1
L.H.S = R.H.S
Hence it is proved.
APPEARS IN
RELATED QUESTIONS
Evaluate the following:
2tan2 45° + cos2 30° − sin2 60°
Express each one of the following in terms of trigonometric ratios of angles lying between
0° and 45°
Sin 59° + cos 56°
Prove that `cos 80^@/sin 10^@ + cos 59^@ cosec 31^@ = 2`
Prove the following
sin θ sin (90° − θ) − cos θ cos (90° − θ) = 0
find the value of :
3sin2 30° + 2tan2 60° - 5cos2 45°
Prove that:
`((tan60° + 1)/(tan 60° – 1))^2 = (1+ cos 30°) /(1– cos 30°) `
If sec A = cosec A and 0° ∠A ∠90°, state the value of A
If A =30o, then prove that :
sin 3A = 3 sin A - 4 sin3A.
Without using table, find the value of the following:
`(sin30° - sin90° + 2cos0°)/(tan30° tan60°)`
Find the value of x in the following: `sqrt(3)`tan 2x = cos60° + sin45° cos45°